Craft c



*ATENT Enron.

CRAFT C. CARROLL, OF NEWV YORK, N. Y.

COMPOSITlON OF MATTER AND METHOD OF PRODUCING THE SAME.

SPECIFICATION forming part of Letters Patent No. 475,382, dated May 24,1892.

Application filed Tune 20, 1891. $erial No. 396,978. (No specimens) ToctZZ whom it may concern.-

Be it. known that I, CRAFT O. CARROLL, a citizen of the United States,residing in the city and county of New York, in the State of New York,have invented a certain new and useful Composition of Matter and Methodof Producing the Same, of which the following is a specification, suchas will enable those skilled in the art to which it appertains to makeand use the same.

This invention relates to an alloy or metallic compound that can bedissolved by mercury and rendered temporarily plastic, so that it can bemolded or shaped into any desired form, and that will by molecularmovement set or harden without shrinkage or expansion, and that will notafterward oxidize, tarnish,

or in any way be affected by atmospheric, sulphurous, septic, or othergases, and that will at the same time have resisting strength, te-

nacity, and malleability sufficient to render it of great value in manybranches of the mechanical arts, and particularly in dentistry as anagent for stopping or repairing decayed or broken teeth, and from whichnew teeth may be formed, and which will, in fact, serve as a substitutefor gold and other substances now used in dentistry, and be superior tomany, if not all, of such substances heretofore employed for suchpurposes.

I have discovered, after long investigation and many experiments withvarious metals, that alloys may be formed of many of the well-knownmetals or combinations thereof and aluminum by mixing them in certainproportions and reducing the product to a powder, which may be readilydissolved by mercury and made into a plastic or semi-solid mass, thusforming an amalgam that can be manipulated into any desired form andpossessing all the qualities hereinbefore specified. The alloys referredto may be composed of aluminum in connection with ost any of thewell-known metalssuch as gold, silver, copper, platinum, tin, and manyotherseither separately or in combinations of two or more of them,according to the product or result required or the purpose for which thesame is intended, which may be as broad as the field of the mechanicarts. In order, however, that the alloys referred to may be amalgamatedor united with mercury, as described, Ifind that it is necessary toemploy with either of the metals or combinations thereof from which itis desired to produce the alloy a proportion of from one-half of one percent. to two per cent. of aluminum, and the remainder must be made up ofthe other substance or substances employed. For instance, alloys of goldand aluminum in the ratio of ninety-eight to ninety-nine (98 to 99) percent. of the former to from two to one (2 to 1) per cent. of the latter,or of silver and aluminum or copper and aluminum in the sameproportions, may be formed, which may be con- Verted into an amalgam inthe manner described. Again, alloys of certain combinations of thesemetals, together with aluminum, may be formed, which may be amalgamatedin the same manner.

For dental and many other purposes I prefer an alloy composed of thefollowing ele ments in the proportions given, viz., silver,

forty-two and three-tenths (42.3) per cent; tin, fifty-two (52) percent; copper, four and seven-tenths (4.7) per cent; aluminum, one (1)per cent. This combination produces an alloy which, when reduced to apowder and dissolved with mercury, forms an amalgam in the form of aplastic mass that has no equal for the purposes of dentistry. It can bemanipulated or formed in any manner desired, readily packed into thecavities of teeth with steel or other instruments, the more easily ifsaid instruments are heated to about 200 Fahrenheit, making a completeand harmonious restoration of decayed, broken, and lost parts of thenatural teeth that subserves all the desirable purposes of a perfecttooth and restores and conserves the same beyond any hitherto-knownamalgamating compound, in that it is easily and speedily manipulated,sets quickly, and becomes very hard and homogeneous, with a strong edgestrength that forms a closely adhering line of union with the toothstructure, making a perfect stopping against the air and fluids of themouth, and that resists to the highest degree any action of oxygen,sulphur, or other materials that deteriorate other 'amalgams used forthe same purpose.

I have long regarded aluminum aspossessing peculiar conservingproperties as an element for an amalgam alloy, if it could only be madeto amalgamate, which hitherto has not been successfully done, as far asmy knowledge goes, but which at length I have accomplished by followingthe law of chemical aflinities, in accordance with the true chemicalequivalency of the metals employed.

In the formula last given for producing an amalgam alloy it is notabsolutely necessary to employ the exact percentages of the parts given,though in doing so a perfectly-satisfactory result is obtained. Thepercentage of aluminum employed may be decreased to one-half of one percent. or increased to two per cent. with perfect safety, and it is alsopossible to slightly vary the percentage of the other elements of thecombination without serious disadvantage, and for some purposes and usesthe element of tin in this formula may be entirely omitted, in whichcase the proportion of silver and copper should preferably bear the sameratio to each other as when the tin is included. In all cases, however,the percentage of aluminum employed should never be less than one-halfof one per cent, and not much, if any, over two per cent.

It is evident that many other alloys in which aluminum forms an elementmay be produced, which may be amalgamated in the manner described, andmy invention is not limited to those herein described; but,

Having fully set forthmy invention, its construction, purposes, anduses, what I claim, and desire to secure by Letters Patent, is- 3 1. Themethod of producing an amalgam r for dental and other purposes, whichconsists in forming an alloy in which aluminum con stitutes an elementand then adding mercury to the alloy, as and for the purposes set forth.4

2. The method herein described of producing an amalgam for dental andother purposes, which consists in forming an aluminum alloy, reducingthe same to powder, and dissolving the powder with mercury, substan- 4}tially as shown and described.

3. An alloy composed of silver, tin, copper, and aluminum in theproportions specified.

4. An alloy composed of silver, tin, copper, and aluminum in theproportions specified 5i and reduced to a powder, as and for thepurposes set forth.

Signed at the city and county of New York, in the State of New York,this 19th day of June, A. D. 1891.

CRAFT o. CARROLL.

Witnesses:

O. L. DAVIS, O. E. ELLIs.

